Smokeless fuel-economizer.



C. W. JOHNS. SMOKELESS FUEL ECONOMIZER; APPLICATION FILED MAY 22. 1911.

Patented Oct. 23,1917.

CHARLES W. JOHNS, OF J ERSEYVILLE, ILLINOIS.

SMOKELESS FUEL-E0010 OMIZER.

Specification of Letters Patent.

Patented Got. 23, 191?.

Application filed May 22, 1917. Serial No. 170,195.

To all whom it may concern:

Be it known that 1, CHARLES W. JOHNS, a citizen of the United States,residing at J erseyville, in the county of Jersey and State of Illinois,have invented certain new and useful Improvements in Smokeless F uel-Economizers, of which the following is a specification.

This invention relates to certain new and useful improvements insmokeless fuel economizers, and has particular reference to improvementsover my prior Patent No. 1,049,100, granted December 31, 1912, whereinthere is provided a pipe positioned exteriorly of the smoke stack fordrawing gas and products of combustion from the stack and subsequentlymixing the same with fresh air. In this construction the mixing ofproducts of combustion with fresh air is performed exteriorly of thefurnace structure so that the gas and roducts of combustion are mixedwith col air. The present invention is designed with a view of heatingthe fresh air simultaneously with the mixing of the same with gas andproducts of combustion.

The primary object of the invention is the provision of an attachmentadaptable for any type of furnace or boiler to be positioned in thesmoke stack thereof insurin perfect combustion of the fuel t erebyreducing the cost of operation as well as eliminatin the smoke nuisance.

A her object of the device is the provision of a regulatable heater andmixer for furnaces which is easily and cheaply installed in a smokestack and is adapted to increase the efiiciency of the furnace byrendering it possible to burn lower grades of coal, the structure beingbeneficial to health and saving waste. I

While the present device is designed for the distribution of pre-heatedair over and below the furnace fire, such is known to be old and thepresent invention broadl covers the mixing of fresh air with pro ucts ofcombustion within the furnace stack, the heating of this mixture thereinbeing suitably controlled as well as its forced introduction into thefurnace.

In the drawing forming a part of this application and in which likenumerals refer to corresponding parts throughout the several views:

Figure 1 is a front elevation of a furnace provlded with the presentdevice parts bethe more ing1 illustrated in central vertical section, an

Fig. 2 is a side elevation thereof partially broken. away.

My invention may be applied to any form of furnace and the same isherein illustrated in connection with the usual form of horizontalboiler furnace 10 having a boiler 11 arranged above the fire box 12 inwhich there is positioned a grate 13 having an ash pit 14 arrangedbeneath the grate. The usual flue doors 15 are arranged forwardly of theboiler 11 While entrance to'the fire box or combustion chamber 12 isobtained through the doors 16, similar doors 17 being arrangedtherebeneath for the ash pity14, it being understood that the .fire box12 is suitably arranged in communication with the upright smoke stack oroutlet flue 18.

A blower or fan 19 operable in any suitable manner is arranged adjacentthe furnace 10 having an outlet pipe 20 tapped into the ash pit 14 as at21 and with a branch pipe 22- arranged with a plurality of nozzles 23entering the front wall of the fire box 12. A regulating damper 24 isprovided in the branch pipe 22 while a similar damper 25 is provided inthe pipe 20 below the said branch pipe.

A mixing device includingapipe 26 is arranged within the stack 18 insubstantial axial relations therewith and connected with the inlet ofthe blower 19 by means of a conduit 27 passing through the adjacent sideof the stack.

The mixer pipe 26 has its lower end portion 28 arranged within theenlarged or flaring base portion 29 of the stack 18 and is provided witha controlling damper 30 spaced from the lower end, while the upper endportion 31 of the mixer 'pipe 26 arranged above the conduit 27 is tappedthrough the side of the stack or smoke outlet flue 18 as at 32 for theadmission of atmospheric air to the mixer 26. An operating lever 33 maybe provided for the damper 30 having a pull cord 34 depending at aconvenient position adjacent the furnace 10, although it will beunderstood that any convenient means that is desired may be arranged forturning the dampers 24, 25, and 30. 1

It will be understood that with the blower 19 in operation, the deviceprovides for the introduction of an excess of heated air through thenozzles 23 into the fire box 12 when fresh coal is being charged intothe furnace and gradually reducing this excess air as the excesshydro-carbons from the fresh coal are burned. When this has beenaccomplished the air supply is changed by closing the damper 24 andopening the damper 25 thereby admitting air below the grate 13 into theash pit 14. The mixer damper 30 is operated in accordance with the draftof the stack 18, the stronger the stack draft, the wider this damper 30must be opened and the weaker the stack draft, the nearer the damper isclosed, The damper 30 regulates the amount of fresh air entering themixer 26 from the inlet 32 as the wider the damper 30 is opened, thesmaller is the amount of fresh air drawn into the mixer end portion 31.The mixer end 28 being central of the upwardly contracting stack portion29 directly receives the heated products of combustion from the fire box12 when the damper 30 is opened while the amount of such ascendingheated gases entering the mixer 26 regulates the amount of fresh airentering the vmixer from the opening 32, which mixture is drawn into theconduit 27 by the suction fan or blower 19. It will be evident that whenthe damper 30 is open to its greatest extent and the stack draft is ofgreat strength and the blower 19 idle, the products of combustion willpass upwardly through the surrounding portion of'the stack 18, and causean inward and downward draft of air through the pipe 26 to mix therewithin the stack and be conveyed therefrom in the usual manner. By partiallyclosing the damper 30, and operating the fan 19, the upward inflow ofgas to the mixer 26 is rendered insuflicient to expel, and prevententrance of the air to the mixer portion 31 so that the gas and air areunited in the mixer, as

well as heated therein by the high temperature maintaining within thestack and be drawn through the conduit 27 by the blower 19 and utilizedin the combustion chamber 12 and ash pit 14: in the manner heretoforedescribed.

By means of my device herein disclosed,

air may be pre-heated to a temperature from 400 to 500 Fahrenheit andadvantageously employed for forced draft purposes. The feeding ofsuperheated air to the fire as well as the returning and refeeding ofthe escaping partially burned gases greatly conserves the fuel andutilizes to the greatest naaaeae extent, all of the heat units containedtherein.

While the form of the invention herein set forth is believed to be thepreferable embodiment of my device as embodying the utilitarianprinciple thereof, it will be nevertheless understood that other formsof the same may be employed without departing from the spirit and scopeof my invention as claimed, such for instance as the positioning of thelower end of the mixing chamber in some other portion of the stack orboiler than the lower flaring portion of the stack as hereinillustrated.

It is noted that it is not intended that any smoke or gases will passout of the open ing 32 upon opening the damper 30 as the said damper isdesigned to be closed when the blower 19 is not in operation but uponopening the damper at such times, the products of combustion would notpass out of the opening 32 as the up-draft of the stack, exceeding thatof the mixer, insures the passing of such products through the stack andoutwardly of the top thereof.

What I claim as new is 1. In a furnace provided with a flue and a grate,the combination with said flue and grate, of an air and furnace-gasmixer arranged within the flue and in communication'with the atmosphere,means for regulating the flow of furnace gases entering the mixer, aconduit communicating with the mixer intermediate the ends of the mixerand having branches discharging above and below the grate, a forceddraft device in said conduit, and means for regulating the flow ofmixture through the respective branches of the conduit.

2. lfn a furnace provided with a flue and a grate, the combination withsaid flue and grate, of an air and furnace gas mixer ar ranged withinthe flue and in communication with the atmosphere, means for regulatingthe flow of furnace gases into the mixer, a conduit member communicatingwith the mixer intermediate the ends of the mixer with its discharge endleading to the furnace, a forced draft device in said conduit member,and means for regulating the flow of mixture from the conduit memberinto the furnace.

In testimony whereof ll affix my signature.

